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Java 百里香-春天。在另一个对象内访问对象属性_Java_Spring_Spring Mvc_Thymeleaf_Spring El - Fatal编程技术网

Java 百里香-春天。在另一个对象内访问对象属性

Java 百里香-春天。在另一个对象内访问对象属性,java,spring,spring-mvc,thymeleaf,spring-el,Java,Spring,Spring Mvc,Thymeleaf,Spring El,我有这门课 public class Guardian { public Guardian() { super(); } private Long id; private String name; .. } public class AlarmNotification { private Long id; private Guardian guardian; } 在我的胸腺细胞模板中 <td class="c

我有这门课

public class Guardian {

    public Guardian() {
        super();
    }

    private Long id;

    private String name;
..
}

public class AlarmNotification {


    private Long id;


    private Guardian guardian;
}
在我的胸腺细胞模板中

<td class="col_name" th:text="${alarmNotification.guardian.name}"></td>

监护人无效。添加三元运算符以处理此情况:

<td class="col_name" th:text="${alarmNotification.guardian == null ? '' : alarmNotification.guardian.name}"/>


AlarmNotification中的监护人为空。您必须初始化guardian才能访问name属性。它是在控制器上设置的,您可以添加控制器代码
<td class="col_name" th:text="${alarmNotification.guardian == null ? '' : alarmNotification.guardian.name}"/>